Sandwich panels are typically formed from a core sandwiched between two face sheets. The core may be relatively thick, yet lightweight, as compared to the face sheets. The face sheets may be relatively thin, yet stiff. Therefore, sandwich panels typically possess relatively high strength and stiffness at relatively low weight.
Because of their relatively high strength and stiffness at relatively low weight, sandwich panels are widely used in various aerospace applications. For example, sandwich panels are used in the construction of aircraft, such as fixed-wing commercial aircraft. Specifically, sandwich panels are used to construct the flooring, walls and bulkheads that define the passenger cabin of an aircraft. Therefore, there is often a need to join one panel to another panel.
A perpendicular joint is often needed where a vertical sandwich panel transitions to a horizontal sandwich panel (e.g., a floor-to-wall transition). The “tab and slot” technique—based on the “mortise and tenon” technique common in carpentry—is one technique used to form a perpendicular joint between two sandwich panels. Specifically, the “tab and slot” technique involves forming slots in one panel and then engaging the slots with corresponding tabs formed on another panel. An adhesive is introduced to bond together the two panels.
Thus, the “tab and slot” technique for joining sandwich panels can be expensive due to the cost of the adhesive. The time required for surface treatment prior to adhesive application, as well as the cure time required after adhesive application, further contributes to the overall cost of using the traditional “tab and slot” technique for joining sandwich panels.
Accordingly, those skilled in the art continue with research and development efforts in the field of sandwich panel joining.